Pledge setup - minimum constraint violation? What the?

Hello Tess-users, 

I'm trying to set up a pledge (without payment) in our system however an error message is preventing me from setting up the pledge in the Contribution Editor.

The pledge is for $3150 to be paid over the next 7 months ($450 a month till the 30 June, 2012) starting from December.

The error message that comes up as I hit the 'schedule' button reads:

Minimum Constraint Violation:

System can not write schedule items for less than $1000

Can someone please explain what this means? What am I doing wrong and how I can get our system administrator to fix this for me?

Any help or suggestions would be very much appreciated!

Thanks,

Katherine

Melbourne Recital Centre